In general, a liquid distribution device is used in petroleum refinery, petrochemistry and fine chemistry, and is used in a scrubber, an absorber, etc., which adopt the principles of distillation, absorption and cooling so as to remove harmful gases or organic matters.
There is a column which is currently industrially used in distillation, absorption, and cooling and separates the desired material through gas-liquid contact. Recently, a divided wall column is used to save energy and reduce the investment cost. The divided wall column has a structure formed by combining two columns into one. The divided wall column is required to distribute the liquid in the upper portion thereof to lower two divided walls in a desired ratio. Here, the liquid distribution device controls the supply ratio of the liquid.
Regarding the above conventional liquid distribution device, the supply ratio of the liquid is determined according to a time during which a feeder stays for a certain time after rotating to both sides by the rotation of the axis at a predetermined angle, that is, according to a ratio of a time period during which the feeder stays in one of both sides to a time period during which the feeder stays in the other of both sides. Therefore, for a time during which the feeder rotates from one side to the other side, the liquid is not continuously supplied, so that surging occurs and the performance of packing is decreased.
Also, since compressed air consumption is increased and durability is deteriorated due to the continuous rotation of the axis, the main parts should be replaced after operation for a certain period of time. While the axis stays for a predetermined time after rotating right and left, the liquid is supplied and the distribution ratio is controlled. However, a difference occurs between the actual time ratio and the distribution ratio, and thus, it is necessary to always correct in advance the difference by the liquid flow test.
Also, in the process of distributing the liquid for the purpose of supplying the liquid, impurities included in the liquid causes errors to occur in the operation of the liquid distribution device.